Is it possible to insert a VBA code module into an existing Excel workbook
from Access 2000?

I need to add a button on certain worksheets (some worksheets, not all) that
will create charts. Unfortunately, I do not own the workbook and have to
append data and charts from a separate Access database. I want to add a
button and code for creation of more charts, but don't know if this is
possible. If I could insert a VBA module into the workbook, that might do
it. If someone could point me in the right direction on this that would be
great.

Thanks in advance.